This invention relates to mechanical seekers, and more particularly, to seekers used in airborne guided missiles.
A guided missile, particularly an air-to-air guided missile, requires a high performance seeker assembly to manuever a radar antenna in the nose of the missile. The severest demands placed on the seeker involve moving the antenna through a wide look angle, maneuvering the antenna in the presence of high G forces, and combining the seeker functions into a small diameter envelope on the order of 5 inches. Also of prime importance is the reliability of the seeker and the cost of the seeker.
Previous orthogonal axis seekers have generally not been able to provide the wide look angles in a small envelope required by state of the art guided missiles. Moreover the offset required of the two orthogonal axes (i.e., the axes do not intersect) produces severe torque requirements on the drive motors due to high lateral G environments. For instance a lateral force of 120 G's causes a five ounce antenna to place a 37.5 pound static load on the bearings and the motors.
Moreover, an orthogonal axes seeker restricts the motors to a limited back and forth motion thereby producing increased torque requirements on the motors.
Therefore it can be appreciated that a reliable guided missile seeker which provides wide look angles in a small envelope yet which is fairly simple in construction is highly desirable.